(1) Field of the Invention
The present invention relates to a sheet guide adjusting apparatus to be used for conveying sheet. materials such as original, e.g., documents, etc., or copies thereof in copy machines, phototelegraphic apparatuse, photo-engraving machines, and the like.
(2) Description of the Related Art
In conventional copy machines, phototelegraphic apparatuses and photo-engraving machines etc., when sheet materials such as original or copies are conveyed therethrough, the sheet materials are guided by keeping the edges thereof in contact with guides, and if a different size sheet material is to be conveyed, the guides are moved to the required positions to accommodate the different size of the sheet materials.
Various ways of adjusting the position of the guides are known; for example, the center-standard method in which the positions of the guides are adjusted on the basis of a center point of the sheet to be conveyed. In this method, a shaft fixed to the center of a machine body is provided with a pinion rotating therearound, a pair of racks having guides, which are in contact with both edges of the sheet, are arranged on both sides of the pinion, and are moved together or apart by the rotation of the pinion in such a manner that the positions of both guides can be adjusted as desired.
In a modification of this center-standard method, a pair of sliding members having guides are fixed to a wire suspended on a plurality of rollers and freely movable, whereby the reciprocal motion of one of the sliding members is transferred to the other sliding member via the wire, and thus the pair of sliding members are moved together or apart in such a manner that the positions of both guides can be adjusted as desired.
Another known method is the edge-standard method, in which the positions of the guides are adjusted on the basis of one side edge of the sheet. In this method, a fixed guide is provided on one side of the machine body and a sliding member having a sliding guide fixed thereto is arranged on the other side of the machine body, and the distance between the fixed guide and the sliding guide is adjusted by moving the sliding member.
As described above, in the conventional sheet guide adjusting apparatuses, positioning the guides to match the size of the sheet is conducted only according to the center-standard method or to the edge-standard method, and a sheet guide adjusting apparatus in which both the center-standard method and the edge-standard method can be conducted is yet to be disclosed. To enable both of the above methods to be conducted in one apparatus, two of the third type of apparatuses mentioned above are arranged on both sides of the machine body and the respective sliding members are moved individually, whereby the distance between both sliding members can be adjusted as desired.